A potent symbol of Japan’s past military prowess, the naval ensign, or war flag, rises again in Toyko Bay. The flag, also used by the army during World War II, stopped flying upon the nation’s surrender to Allied Forces in 1945. Japan’s constitution, adopted two years later, prohibits acts of military aggression. But the flag was readopted in 1954 and its use was resumed by the military, now called the Japanese Self-Defense Forces. Once a bitter foe but now an ally, the United States presses Japan to play a more active role in a new global theater of war—this one against terrorism.